Automatic cut-off valve



J. F. CURRIVAN AUTOMATIC CUT-OFF vALvE Filed oct.3o, 1924 March 1,5, 1927.

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UNITED 'STATES l 1,620,816 PiixrizNT4 OFFICE.'

J'QHN F. CURA'RIVAN, 0l CAMBRIDGE,l MASSACHUSETTS.

AUTOMATIC CUT-OFF VALVE.v

application alga october ao, 1924. seiiai 1u. 746,906.

This invention relates to safety valves adapted to be placed in the supply lines for illuminating gas, preferably adJacent the nts of entry of such lines through the l foundation walls of `a house or building, and ada ted to interrupt the iiow of gas from suc supply liliesto the distribution lines in the buildingin` case of fire -or other emergency. c

The object of the present invention .is the provision of an improved safety. device .of the character mentioned, wherein -the device may operate either due to the presence of excessive temperature near by or at remote points, wherein the device may be readily reset, in which the valve casing housin the valve may be provided with walls w olly composed of metal, and whereinA all possibility of 'the breaking of electricl circuits within the gas system may be eliminated.

According Ito the present invention the safety valve preferably comprises a casing whose walls are entirely metallic and which houses a valve biased towards, or having a constant tendency to assume, a closed position but maintained in open position by means including a fusible element. The

valve may be pivotally supported and swingl upon release to a closed position in a direction such that the gas tending to enter the distribution piping in the building will maintain the valve tightly closed. Again, the mechanism is preferably constructed in such manner that it may be automatically rendered operative either by excessive heatv at the point where it is disposed or by the existence of an excessive temperature at various points throughout the building, or may be manually controlled if desired. For the purpose of effecting a control of the valve to permit its closure, destruction of a fusible or heat destructible element is preferably relied on; and such fusible element is preferably arranged to have'the heat necessary for its destruction transmitted to it either when the walls of the casing of the valve mechanism are exposed to heat, or upon a localized heating of the supporting means for the fusible element which may preferably be accomplished by an electrically heated coil arranged outside the casing of the valve mechanism.' If desired 'the release of the valve mechanism may be accomplished under certain conditions by the direct effect of excessive heat and under other conditions. by electro-magnetic means. In

either case, however, it is designed that mechanism shall be rendered operative automatically by the existence of too high a temperature at the casing proper or at a point remote from the casing. It is further designed that the device shall be'readily reset after being caused to operate and that 1n its destruction thel *fusibleY element shall not have an opportunity to form an excrescence upon the valve which may interfere with its closing. In the accompanying drawingsv in which there are shown for purposes of illustration two forms which the invention may assume 1n practice,

Fig. 1 is a central vertical section through one illustrative form of the safety device together with a diagrammatic showing of certain circuits:

Fig. 2 is a horizontal section on the line 2-2 of Fig. 1; and

Fig. 3 is a fragmentary sectionalA view corresponding to a portion of Fig. 1 showing a modified form of construction.

In lthe form of the invention shown for purposes of illustration inFigs. 1 and 2, a casing 1 having a closure member 2 provides a chamber 3 which is arranged between and serves to connect a gas supply line 4 with the distribution line 5 in a building, the casing 1 being preferably connectedk to the line 4 at a point just inside Athe usual manual shut off valve. Within the casing 1 and above the bottom wall 6 of the latter there is mounted loosely as at 8 a valve member 9 which has a conical portion 10 adapted when the valve assumes the dotted line position shown yin Fig. 1 to cooperate with the valve seat 11 and to interrupt the iiow of gas in the supply line 4 to the distribution line 5, the valve seating as will be obvious in 'a direction such that the pressure of the gas in the line 4 will aid in rendering it more effective in its action. The casing 1 obviously need not be made `in two parts but may be 'cast integral, and when this is done the valve 9 may be inserted through the opening for the pipe 4 and held in position with the finger while the pin 8 is inserted. For the purpose of normally maintaining the valve 9, which is biased towards closed position by gravity, in open position means are provided including an opening`12 in the valve member which provides an edge 13 which cooperates'vwith an abutment member 14 composed of some material which bends readily, fuses, or'is destroyed, b the application of heat.- The abutment `1 is supported in a metallic plug which is threaded.

as at 16 into the wall of the casing through which the pipe 4 opens into the latter. At its outer end plug 15 comprises a cylindrical portion 17 which is surrounded by a heating coil 18 constructed in a familiar manner aud adapted to be supplied with electric current from any suitable source 19 upon the closure of a manually controllable switch mechanism 20 or upon the closure of any one of a series of thcrmostatic switches 22` thc closure of the manual switch or the thermostatic switches `comun-ting the leads 23 and 24 from the coil 18 in a closed circuit with the source of cur1'ent`19.

For the purpose ol' enabling the niovemcnt of the valve 9 to open position after it has once been closed a threaded removable plug 25 is connected by a chain 26 and hook or eve 27 with the rear side of the valve 9 so that upon unscrewing the plug 25 the chain 26 may be drawn to opcu the valve and move the latter into the full line position shown in Fig. 1. A second opening 30 having a closure plug 3l is arranged adjacent the distribution line 5, through which opening a rod or other implement may 'be inserted upon removal of the plug 31 to force the valve to the position shown in full lines in Fig. 1. It will be observed that the recess 12 will collect the molten material from the element 14 and prevent possibility of the latter adhering to the surface of the `valve 10 and causing an excrescence which would prevent closure of the valve.

The mode of operation of this illustrative form of the invention is as follows: Let it be assumed that a fire breaks out near the casing 1. In this event the walls of the casing \will become hot and the heat will be conducted and radiated to the abutment member 14. As a result the latter will be melted and cease to hold the valve 9 in open position. Thereupon the valve 9 will close by gravity and the conical f surface 10 seating within l the surface 11 will eli'ectively interru t the flow of gas into the house piping. wing to the fact that the fused metal drops into the recess 12 the valve will seat surely and can not have its closing movement interfered with by the possible adherence of the metal to the surface 10. In the event that the fire breaks out at a point remote from the casing 1, but adjacent one ofthe thermostats 22, which may be arranged in any desired number about the house or building, the heat will cause the affected thermostat to close a circuit ineludin the source of current 19, the coil 18 and t e wires 23 and 24. As a result the resistance coil 18 will be heated and will heat the element 15 and this heat, conducted longitudinally of the latter, will melt the fusible material .14 and permit the valve to close. It' will also be obvious that in the event of the discovery of fire by a person in the house the switch 20 may be nwchauism, e'ectro-magnetc means is relied ou to move the fusible element to a position to release -the valve. In this illustrative form a fusible abutment 14 cooperates with a shoulder '13 upon a valve 9 and in the. event of'hcatiug of the casing 1- the fusable element 14 will be destroyedand the valve 9 allowed to close just as in the first illustrative mechanism disclosed. The member 14 is mounted at the lower end to an armature 35 which is reciprocable in a dielectric tube 36 and which is prevented from dropping downwardly to an excessive distance by a pin 37 extending into an annular groove 38. A solenoid 39, having leads 23 and 24 is connected in circuit just as was the coil 18 in the form shown in Fig. 1. It will be evident that in the event of the closure of a circuit between a source of current and leads 23 and 24 thejsolenoid 39 will be energized and the core 35 drawn into the latter and that the bodily upward movement of the element 14 will release the valve 9A and permit it to close.

In the event that the abutment element of either illustrative form of the invention is rendered inoperative by the action of heat,

so that it no longer retains the valve in open position, it may obviously lreadil be replaced by removing its associate mechanism and replacing the element. From the foregoing description it will also be evident that `whether the fire occurs adjacent the safety device proper or at a point remote therefrom the admission of gas to the building may be s'urely interrupted.

While the forms of mechanism here shown and described are well adapted to fulfill the objects primarily stated, it is to be understood, that it is not. intended to confine the invention to the forms or embodiments herein disclosed, for it is susceptible of embodiment in various forms all coming within the scope of the claims which follow.

I claim:

1. A safety valve for gas pipes including a valvecasing, a valve therein biased towards closed position, an abutment element readily deformable by the action of heat normally maintaining said valve in open position, supporting means for said abutment member relative to which said valve is movable during closing and means carried by but exterior to said casing for rendering said abutment element inoperative to hold said valve open.

2. A safety valve for gas pipes including a valve casing, a valve therein biased towards closed position, an abutment element readily deformable by heat normally maintaining said valve in open position, supporting means for said abutment member relative to which said valve is movable during closing and means including a coil carried by but exterior to said casing and means for causing a flow of current therethrough for rendering said abutment element inoperative to hold said valve open.

A safety valve for gas pipes including a valve casing, a valve therein biased towards closed position, an element readily deformable by heat normally maintaining said valve in open position, and electric heating means carried by but exterior to said casing for effecting destruction of said element whereby said valve may close.

4. A safety valve for gas pipes including a valve casing, avalve therein biased towards closed position, an element normally operative to hold said valve in open position, said element becoming inoperative to hold the valve open when subjected to excessive heat and means arranged outside said casing for generating heat to effect destruction of said element.

5. A safety valve for gas pipes including a. valve casing, a valve therein biased towards closed position, a fusible element in said casing normally operative to hold said valve in open position, but deformable on excessive heating of said casing, means arranged outside said casing for generating heat to effect destruction of said element, and means at a distance from said casing for rendering said last mentioned means operative.

6. A device of the class described comprising a casing arranged between a supply line and a distributing line and affording a chamber, a valve in said chamber biased towards closed position, means including a heat deformable device for holdi g said valve in open position, and means ncluding an element forming a removable portion of said casing, and a fiexible connection between said element and said valve for moving said valve to open position.

7. A device of the class described comprising a casing having wholly metallic walls arranged between a supply line and a distributing line and affording a chamber, a valve in said chamber biased towards closed position, means including a heat destructible device supported by a wall of said casing for holding said valve in open position, and means for applying a localized heat to a portion of the wall of said casing to effect deformation of said heat deformable element' whereby said valve may close.

8. A device of the class described comprising a casing forming a connection between a supply line and a distributing line, a valve in said casing biased towards closed position, and a fusible element cooperating with said valve to hold the latter open, said mechanism providing a recess to receive said fusible element on fusion of .the latter.

9. A device of the class described comprising a casing forming a connection between a suppl line and a distributing line, a valve in sai casing biased towards closed position, and a fusible element engaging said valve to hold the latter open, said valve having a recess to receive said fusible element on fusion of' the latter.

Signed by me at Boston, Massachusetts, this 24th day of October, 1924.

JOHN F. CURRIVAN. 

